Abstract：The flow stress behavior of 7050-T7451 aluminum alloy at high temperature and high strain rate was investigated by split Hopkinson pressure bar (SHPB) and quasi-static test system. The strain hardening parameters were obtained by the quasi-static test experiment data.The strain rate hardening parameter at various strain rates (400-2500s-1) and room temperature,and the thermal softening parameter at various temperatures where strain rate is 2500s-1,were obtained by the split Hopkinson pressure bar experiment data.A new thermal softening equation is proposed to revise the Johnson-Cook constitutive equation ,where the a quintic polynomial equation is choosed as the new thermal softening equation.According to the comparison between predict curves and experiment curves of stress-strain at various temperatures,the modified constitutive equation can fit the experiment date well.
滑勇之, 关立文, 刘辛军, 崔海龙. 铝合金7050-T7451高温高应变率本构方程及修正[J]. 材料工程, 2012, 0(12): 7-13.
HUA Yong-zhi, GUAN Li-wen, LIU Xin-jun, CUI Hai-long. Research and Revise on Constitutive Equation of 7050-T7451 Aluminum Alloy in High Strain Rate and High Temperature Condition. Journal of Materials Engineering, 2012, 0(12): 7-13.
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